Why is my laptop battery life so bad?

I own a Dell Latitude e6430 (bought in 2012, Windows 10 Pro 64 Bit, i7 3rd Gen, 16 GB Ram, NVIDIA NVS 5200QM). I got it a few years ago to use it for school. Since the battery was 8 years old, I bought a new one, but the battery life was still under 2 hours. Since I only used my laptop on the power cord at the time, it didn't really matter. But now I've started to study and have to lug my laptop around from A to B (I don't mind the weight) and don't always have a power outlet ready. How can I increase the battery life so that I can work with it for at least 5 hours (Office Apps)? Switching on the "longest battery life" and dimming the display are not much help…

The battery is relatively weak and the hardware from back then draws a lot of power.

The i7 and the 5200qm are the culprits.

The i7 alone used to draw 45-65 watts.

The battery always gets a little bit weaker after a charging cycle and you mean that it is relatively old. Would recommend buying a new battery that should be easy to get out of.

I've already done that (is already in the question)

Thanks for your answer. Is there anything I can do to increase the battery life? My brother, who gave me the laptop, told me that the battery was better.

Oh, I didn't see that.

Well, go to energy saving mode in Windows and if possible always switch off the graphics card and use the iGPU from the i5.

More is not really possible.

Somehow you should be able to do something that makes the battery life "normal". I can't even watch a lecture without hanging on the cable…

Yes, the battery life will be 2 hours, I assume?

This is normal with laptops this old. The chips are relatively large, inefficient and use a lot of electricity. Especially old CPUs, GPUs and displays.

The batteries are usually not Li-Ion but Ni-Mh. Also relatively bad for laptops.